George Bush yesterday suffered a blow to his argument that the removal of Saddam Hussein had made Americans safer after he ordered the release of an intelligence report warning the war in Iraq had become a "cause celebre for jihadists".

Mr Bush's decision to declassify a small portion of a leaked National Intelligence Estimate, six weeks before the midterm elections, was seen as an attempt to get in front of Democratic critics, led by Bill Clinton, who accuse the administration of not doing enough to catch Osama bin Laden.

After five years of relative civility, the unspoken entente cordiale between the Bush and Clinton administrations to avoid assigning blame for the 9/11 attacks came to an abrupt end yesterday, with both leaders and their aides fighting for their respective legacies. But Mr Bush's "war on terror" narrative was contradicted by the report.

"The Iraq jihad is shaping a new generation of terrorist leaders and operatives; perceived jihadist success [in Iraq] would inspire more fighters to continue the struggle elsewhere," it said.

"The Iraq conflict has become the 'cause celebre' for jihadists, breeding a deep resentment of US involvement in the Muslim world. If this trend continues, threats to US interests at home and abroad will become more diverse, leading to increasing attacks worldwide."

The report, reflecting a consensus of 16 intelligence agencies, acknowledged some US success in disrupting al-Qaida. But it said these gains were outweighed by other factors, fuelling al-Qaida's spread: anger at corrupt Muslim regimes, anti-US sentiment, and a decentralised leadership that made it harder to penetrate.

It also predicted further attacks in Europe as "extremist networks inside the extensive Muslim diasporas in Europe facilitate recruitment and staging".

The damaging assessment was expected to intensify the struggle to apportion blame in the war on terror in the run-up to November congressional elections.

Democrats have been energised by the row with strategist James Carville saying the party had gained a "spinal implant".

An informal truce between Republicans and Democrats began unravelling this month when an ABC docu-drama portrayed Clinton-era officials as being unconcerned about al-Qaida.

Democrats denounced the programme, forcing the network to make changes, but Mr Clinton reserved his full wrath for last weekend when he told Fox television he had done more than Mr Bush to try to kill Bin Laden. "That's the difference in me and some, including all of the right-wingers who are attacking me now," he said. "They ridiculed me for trying. They had eight months to try, they did not try."

Allies on both sides have since waded in. In New York, secretary of state, Condoleezza Rice, accused the Clinton administration of failing to leave a plan for fighting al-Qaida. But a few blocks away from the White House Ms Rice's Clinton-era predecessor, Madeleine Albright, was accusing Mr Bush of adopting damaging policies because of his strong beliefs.

"If certainties such as the war in Iraq and the axis of evil are based on a religious belief that God is on our side - versus we should be on God's side as Lincoln said - then certitude creates foreign policy problems," Ms Albright said.